It doesn't really matter, it's pretty much just because they're both old white guys with moustaches, but he was a character created for the stage and TV by Richard Hearne.

*Hearne assumed the character of "Mr Pastry" – an old man with a walrus moustache, dressed in a black suit or raincoat and with a trademark bowler hat. Each week, the bumbling old man would have adventures, partly slapstick, partly comic dance, with two young friends. Jon Pertwee also starred in the show in a variety of roles.*